Collapsible saw

ABSTRACT

A collapsible saw ( 10 ) comprising a blade ( 20 ) and a frame construction ( 30 ) formed of parts ( 31, 32, 33 ), whereto the blade ( 20 ) is attachable and which frame construction ( 30 ) can be transformed to a smaller form for e.g. transportation purposes and to at least partly cover the blade ( 20 ) when the saw ( 10 ) is not used. The parts ( 31, 32, 33, 34 ) of the frame construction ( 30 ) of the saw ( 10 ) are attached to each other and the blade ( 20 ) by means of fixing members ( 21, 22, 23, 24, 35 ), at least one of which is a fulcrum pin ( 21, 22, 23, 24 ), a bolt or corresponding allowing a turning motion between the parts, and/or that the saw ( 10 ) is collapsible and can again be turned into the sawing condition without detaching the fixing members.

OBJECT OF THE INVENTION

The invention relates to a collapsible saw comprising a blade and abow-like frame construction formed of parts, whereto the blade isattachable and which frame construction can be made smaller for e.g.transportation purposes and to at least partly cover the blade when thesaw is not being used.

PRIOR ART

To decrease the size of a saw and to facilitate the transportationthereof is inevitable for e.g. picnic saws. It would as well be usefulto decrease the dimensions of e.g. wood and iron saws, which also haveto be transported. A smaller size is also practical for storagepurposes.

In picnic-saws, many kinds of solutions have been developed, the purposethereof being to include the sharp teeth of the saw inside theconstruction in such a way that they may not cause any damage duringtransportation. In numerous known collapsible bow saws, the blade partis detachable and the bow-like frame part is collapsible. Afterdetaching the blade, the collapsible frame part is folded to thetransportation position and the blade is secured e.g. by slipping itinto a tube belonging to the frame part or by pushing it into a suitablegroove.

However, no such solutions have been developed for the conventional bowsaw constructions. The transportation and storage of these saws is stilldifficult, as the saws are fairly big and have a difficult shape.Further, there is no lasting and safe blade cover available for bowsaws.

An iron saw also requires a lot of space in the utensil box, due to itsdifficult shape. Although the blade of an iron saw is not as sharp asthat of wood saws, a blade cover would nevertheless be good to have. Nolasting and safe blade cover is available for iron saws, either.

A disadvantage of known collapsible saws, which usually are picnic saws,is that at least one part of the blade or another part of the saw has tobe detached before the saw can be transformed into the transportationposition. However, the detaching and assembling of the saw istroublesome. Patent publications U.S. Pat. No. 3,954,127, U.S. Pat. No.5,440,816 and U.S. Pat. No. 2,930,420 disclose saw solutions, which arecollapsible in such a way that the blade and/or a part of the blade'sbow are detached or moved aside. In such a case, however, the bow of thesaw has to be broken by unfastening or loosening a member that fixes thepart of the bow, such as a nut or a bolt.

In collapsible form the saws are more practical in view oftransportation, but at the same time the collapsible form includesanother disadvantage. Numerous known picnic saws have the shape of atriangle, whereby the distance between the blade and the bow is short.This kind of a saw can not be used for sawing thick wood.

PURPOSE OF THE INVENTION

The purpose of this invention is to provide a collapsible saw devoid ofthe above-mentioned disadvantages.

CHARACTERISTICS OF THE INVENTION

The collapsible saw according to the invention is characterised in thatthe parts of the bow-like frame construction of the saw are attached toeach other and the frame construction is attached to the blade part bymeans of attaching members, at least one of which is a fulcrum pin, boltor the like allowing a turning motion between the parts, and/or at leastone attaching member is a slide or a corresponding member allowing atransfer motion between the parts, so that the saw is immediatelycollapsible and can again be transformed into the sawing conditionwithout detaching the parts of the frame construction or the attachingmembers between them.

This kind of saw according to the invention is easily transformed intothe transporting position without detaching the blade or any other partof the saw.

Most preferably, the blade is simultaneously covered so that the sharpteeth of the blade do not cause harm during the transportation. Thus,the blade of the saw is not allowed to get blunt. Accordingly, the sawis easy to turn into the operation condition again, as the blade has notbeen detached from the frame construction of the saw. The constructionaccording to the invention is particularly advantageous in picnic saws,but nevertheless just as well in conventional bow saws and iron saws.

EMBODIMENTS OF THE INVENTION

A preferred embodiment of the collapsible saw according to the inventionis characterised in that

-   -   the collapsible frame construction of the saw comprises a lever        part, by turning of which the bow part of the saw is collapsible        and can be transformed into the transportation position,    -   and that by turning the lever part into the opposite direction,        the bow part of the saw can be transformed into the sawing        position, whereby the lever part simultaneously acts as a        tightening lever for the blade of the saw.

A second preferred embodiment of the invention is characterised in thatthe turnable lever part of the frame construction is both a tighteninglever for the blade when the saw is turned into the operating positionand a cover for the teeth when the saw is collapsed.

A third preferred embodiment of the collapsible saw according to theinvention is characterised in that the lever part turnable to cover theteeth is attached to the handle part of the frame construction.

A fourth preferred embodiment of the collapsible saw according to theinvention is characterised in that the lever part turnable to cover theteeth is attached to the front piece of the frame construction.

A fifth preferred embodiment of the collapsible saw according to theinvention is characterised in that the length of the frame constructionof the collapsible saw when in collapsed position is essentially thesame as the length of the blade of the saw.

A sixth preferred embodiment of the collapsible saw according to theinvention is characterised in that the shape of the frame constructionof the collapsible saw when in the sawing position is mainly aquadrangle, such as a rectangle or parallelogram, and that the frameconstruction when in collapsed form has essentially the shape of theblade of the saw and a size only slightly bigger than the blade of thesaw.

A seventh preferred embodiment of the collapsible saw according to theinvention is characterised in that when the frame construction of thesaw is collapsed, the lever part turns to cover the blade from the sideof the teeth.

A further preferred embodiment of the collapsible saw according to theinvention is characterised in that when the frame construction of thesaw is collapsed, the lever part turns to cover the blade of the sawfrom the side opposite to the teeth.

EXEMPLARY EMBODIMENTS

In the following, the invention is described by means of examples withreference to the accompanying drawings, of which

List of the Drawings

FIG. 1 illustrates a collapsible saw according to the invention in thesawing position as a perspective view.

FIG. 2 illustrates an embodiment of the collapsible saw in side view.

FIGS. 3-5 illustrate the various stages of collapsing the saw of FIG. 2.

FIG. 6 illustrates the saw of FIG. 2 in collapsed form.

FIG. 7 illustrates a second embodiment of the collapsible saw in sideview.

FIGS. 8-9 illustrate the various stages of collapsing the saw of FIG. 7.

FIG. 10 illustrates the saw of FIG. 7 in collapsed form.

FIG. 11 illustrates a third embodiment of the collapsible saw in sideview.

FIGS. 12-13 illustrate the various stages of collapsing the saw of FIG.11.

FIG. 14 illustrates the saw of FIG. 11 in collapsed form.

FIG. 15 illustrates a fourth embodiment of the collapsible saw in sideview.

FIGS. 16-19 illustrate the various stages of collapsing the saw of FIG.15.

FIG. 20 illustrates the saw of FIG. 15 in collapsed form.

FIG. 21 illustrates a fifth embodiment of the collapsible saw in sideview.

FIGS. 22-23 illustrate the various stages of collapsing the saw of FIG.21.

FIG. 24 illustrates the saw of FIG. 21 in collapsed form.

FIG. 25 illustrates a sixth embodiment of the collapsible saw in sideview.

FIGS. 26-27 illustrate the various stages of collapsing the saw of FIG.25.

FIG. 28 illustrates the saw of FIG. 25 in collapsed form.

FIG. 29 illustrates a side view of a saw according to a sixth embodimentin collapsed form.

FIGS. 30-34 illustrate the various stages of bringing the saw of FIG. 29into the sawing condition.

FIG. 35 illustrates the saw of FIG. 29 in the sawing position.

FIG. 36 illustrates a side view of a saw according to a seventhembodiment in collapsed form.

FIGS. 37-40 illustrate the various stages of bringing the saw of FIG. 36into the sawing position.

FIG. 41 illustrates the saw of FIG. 36 in the sawing condition.

FIGS. 42-49 illustrate details of various embodiments of the saw.

DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates in the sawing position a collapsible saw 10comprising a blade 20 and a bow-like frame construction 30 holding theblade 20 fixed. The conventional blade 20 is attached to the frameconstruction 30 in a conventional way so that fixing pins 21 a ands 21 bor corresponding fixing members have been pushed through holes in bothends of the blade 20.

The frame construction 30 of the saw 10 of FIG. 1 comprises a handlepart 31, a front piece 32, a support body 33 and a lever part 34, whichis attached to the handle part 31 by means of a fulcrum pin 24. Thesupport body 33 connects the handle part 31 and the front piece 32. Thesupport body 33 is connected on one end by means of a fulcrum pin 22 toa conduit 35 in the handle part 31, said conduit being formed of anelongated opening. The fulcrum pin 22 is movable in the conduit 35.

The opposite end of the support body 33, in its turn, is connected tothe front piece 32 by means of a fulcrum pin 23. FIG. 1 shows that thesupport body 33 is actually formed of two separate support body halves,wherebetween the handle part 31, the front piece 32 and the lever part34 are arranged.

In the collapsible saw 10 of FIG. 1, both the handle part 31 and thelever part 34 are provided with grooves 36 a and 36 b, which are ofgreat significance in covering the teeth 25 of the blade 20. Asillustrated in the following figures, the handle part 31 and the leverpart 34 are turnable onto the blade 20, so that the sharp teeth 25 arecovered in the grooves 36 a and 36 b.

FIG. 2 illustrates an embodiment of the collapsible saw 10 in the sawingposition in side view. The lever part 34 of the frame construction 30 isthen turned between the halves of the two-piece support body 33, wherebythe blade 20 of the saw is tightened. The collapsing of the saw 10begins by lifting the lever part 34 so that it turns around the fulcrumpin 24, as illustrated in the following figures.

In FIG. 3, the lever part 34 of the collapsible saw 10 is liftedupwards, whereby the front pieces 32 and the support body 33 belongingto the bow-like frame construction are turned towards the blade 20 ofthe saw.

In FIG. 4, the support body 33 is pressed towards the blade 20 so thatthe fulcrum pin 22 moves in the conduit 35 in the handle 31 towards theblade 20 of the saw.

In FIG. 5, the handle part 31 and the lever part 34 are turned aroundthe fulcrum pin 22 so that the handle part 31 and the lever part 34 arepressed towards the teeth 25 of the blade 20.

In FIG. 6, the handle part 31 and the lever part 34 of the collapsiblesaw 10 are pressed against the blade 20 of the saw so that the bladesare covered in the grooves of the handle part 31 and the lever part 34,which grooves are more clearly shown in FIG. 1.

An essential thing in the saw 10 illustrated in FIGS. 2-6 is that duringcollapsing and bringing the saw 10 into the sawing condition, no part ofthe saw 10 needs to be detached. Every operation can essentially beperformed in such a way that the parts 31, 32, 33 and 34 of the frameconstruction 30 are turned in relation to the blade 20 and in relationto each other around the joints 22, 23 and 24 between the parts andaround the fixing pins 21 a and 21 b of the saw blade. In the embodimentillustrated in FIGS. 2-6, the handle part 31 is, in addition to theturning fulcrum pins, further provided with an elongated opening 35acting as a conduit for the fulcrum pin 22 located in the end of thesupport body 33.

The collapsible saw 10 of FIG. 6 is brought into the sawing condition inaccordance with FIGS. 2-6, but in the opposite succession. When startingfrom the situation of FIG. 6, the handle part 31 and the lever part 34attached thereto by means of a joint 24 are first turned in accordancewith FIG. 5 around the fulcrum pin 22 anticlockwise. As a fulcrum pin 24is also arranged between the fulcrum pin 22 of the lever part 34, thelever part 34 simultaneously turns around the fulcrum pin 24.

In the position shown in FIG. 4, the handle part 31 of the saw 10 isturned to such an extent that it is directed upwards in FIG. 4. Thelever part 34 is also turned so that the supporting surfaces 38 a and 38b between the lever part 34 and the fulcrum pin 22 are almost attachedto each other. After this, the support body 33 is lifted upwards in FIG.4, whereby the fulcrum pin 22 in the end of the support body 33 is movedto the opposite end of the conduit 35 into the position illustrated inFIG. 3.

When the lever part 34 of the saw 10 is pressed downwards in FIG. 3between the halves of the two-piece support body 33, the frameconstruction 30 of the saw 10 is tightened and a tensile stress requiredfor sawing is formed in the blade 20. After that, a fixing loop 39 inthe support body 33 is turned onto the lever part 34 so that it is fixedin place and the saw 10 is in the sawing condition illustrated in FIG.2.

FIG. 7 illustrates in the sawing position another embodiment of thecollapsible saw 10, in which a shaft part 37 is arranged between thesupport body 33 and the lever part 31, which shaft part is connected tothe handle part 31 by means of a fulcrum pin 26. When the lever part 34of the frame construction 30 is turned between the halves of thetwo-piece support body 33, the saw blade 20 is tightened. In thisembodiment, too, the lever part 34 is fixed in place in the support bodyby means of a fixing loop 39.

FIG. 8 illustrates how the collapsing of the saw 10 begins, where thelever part 34 has first been detached from the fixing loop 39 of thesupport body, after which the lever part 34 is lifted so that it firstturns slightly around the fulcrum pin 24. When the lever part 34 islifted further, the lever part 34 and the handle part 31 together turnaround the fixing pin 21 a of the blade 20. Then the front pieces 32 andthe support body 33 belonging to the frame construction are turnedtowards the blade 20 of the saw.

In FIG. 9, the lever part 34 and the handle part 31 together are furtherturned around the fixing pin 21 a of the blade 20 so that the lever part34 and the handle part 31 approach the blade 20 from the side of theteeth 25.

In FIG. 10, the handle part 31 and the lever part 34 of the frameconstruction 30 of the collapsible saw 10 are pressed against the blade20 so that the blades are covered in the grooves of the handle part 31and the lever part 34.

Also, the saw 10 illustrated in FIGS. 7-10, can be collapsed and turnedinto the sawing condition without detaching any parts. In thisembodiment, the handle part 31 is also devoid of an elongated opening,such as in the embodiments of FIGS. 2-6. When bringing the saw 30 intothe sawing condition, the parts 31, 32, 33, 34 and 37 of the frameconstruction 30 are only turned in relation to each other around thejoints 22, 23, 24 and 26 between the parts. Further, the front piece 31and the handle part 32 are turned around the fulcrum pins 21 a and 21 bin the ends of the blade 20.

The saw 10 of FIG. 10 is brought into the sawing condition in accordancewith FIGS. 7-10, but in the reverse succession. When starting from thesituation of FIG. 10, where the saw 10 is in the transporting position,the handle part 31 and the lever part 34 connected thereto by means of ajoint 24 are first turned in accordance with FIG. 5 anticlockwise. Theshaft part 37 connecting the handle part 31 and the support body 33thereby follows the motion. The turning of these parts mainly takesplace around the fulcrum pin 21 a in the end of the blade 20, whichfulcrum pin is nevertheless not shown in FIGS. 10 and 9, because it isbehind the support body 33 and the shaft part 37: However, FIG. 8clearly illustrates that the handle part 31 and the lever part 34 areturned around this fulcrum pin 21 a.

In the situation of FIG. 8, the lever part 34 has already turnedanticlockwise to such an extent that the support surfaces 38 a and 38 bof the handle part 31 and the lever part 34, which support surfaces areclearly shown in FIG. 9 and which are directed towards each other, havebeen pressed against each other. When the lever part 34 is furtherturned in FIG. 8 anticlockwise, it is pressed between the halves of thetwo-piece support body 33 against the shaft pin 22 in accordance withFIG. 7, simultaneously tightening the blade 20. This situation isclearly seen also in FIG. 1, the saw 10 of which has a correspondingconstruction. This constructional detail is later illustrated in moredetail in FIG. 49. When the lever part 34 is fixed into the support body33 by means of the fixing loop 39, the saw 10 is turned into the sawingcondition without a need to detach any parts or joints of the saw 10.

FIG. 11 illustrates a third embodiment of the collapsible saw 10 in thesawing position, where the lever part 34 or the frame construction 30 isconnected to the front piece 32 by means of a fulcrum pin 23. The front32 piece is in this embodiment a two-piece construction in such a waythat the parts 32 a and 32 b of the front piece 32 are connected to eachother by means of a fulcrum pin 27. The lever part 34 of the frameconstruction 30 is in FIG. 11 turned to be in connection with thesupport body 33, whereby the blade 20 is tightened.

In FIG. 12, the collapsing of the saw 10 has been started by lifting thelever part 34 so that it is turned around the fulcrum pin 23. Thereby,the handle part 31 and the support body 33 are turned towards the blade20 and simultaneously the parts 32 a and 32 b of the front piece 32 areturned as shown in FIG. 12.

In FIG. 13, the lever part 34 has been turned further so that the handlepart 31 turns onto the blade 20 in FIG. 13 from above and the lever part34 turns onto the blade 20 in FIG. 13 from below.

In FIG. 14, the saw 10 is in collapsed form, whereby the handle part 31and the lever part 34 form a cover for the blade 20. The teeth 25 of theblade 20 are covered in the groove of the lever part 34 in the length ofthe lever part 34 in such a way that the blade is covered from thedirection of the teeth of the blade. The rest of the blade 20 goes intothe groove in the handle part 31 from the back side of the blade 20. Asthe groove of the handle part 31 is adequately deep, the blade 20 iswell covered in this position as well.

The saw 10 illustrated in FIGS. 11-14 is collapsed and again broughtinto the sawing condition without detaching any part of the saw 10. Inthe way illustrated in the previous figures, the collapsed saw 10 ofFIG. 14 is brought into the sawing condition in such a way that thelever part 34 is turned in FIG. 14 anticlockwise in the way shown inFIGS. 13 and 14. Thereby, the parts 32 a and 32 b of the front piece ofthe frame construction 30 are turned to each others' extensions and thelever part 34 is turnable between the halves of the two-piece supportbody 33, whereby the blade 20 is tightened. The saw 30 is ready forsawing, when the fixing loop 39 of the support body 33 is fixed in thelever part 34.

FIG. 15 illustrates in the sawing position a fourth embodiment of thecollapsible saw 10, wherein the lever part 34 is connected to the frontpiece 32 by means of a fulcrum pin 23. In this embodiment, both thehandle part 31 and the front piece 32 are formed of two parts. The parts31 a and 31 b of the handle 31 part are connected to each other by meansof a fulcrum pin 28 and the parts 32 a and 32 b of the front piece 32are connected to each other by means of a fulcrum pin 27. The lever part34 of the frame construction 30 is in FIG. 15 turned to be in connectionwith the support body 33, whereby the blade 20 is tightened.

In FIG. 16, the collapsing of the saw 10 has been started by lifting thelever part 34 so that it turns around the fulcrum pin 23.

FIG. 17 illustrates a situation where the lifting of the lever part 34is continued, whereby the parts 31 a and 31 b of the handle part 31 andthe parts 32 a and 32 b of the front piece 32 are turnable in the wayillustrated in FIGS. 17 and 18. Thereby the support body 33 approachesthe blade 20.

In the embodiment of the saw illustrated in FIGS. 15-20, referencenumeral 43 shows a place for a fixing pin or other correspondingfixation. As the front piece is formed of two parts 31 a and 31 b, itsstaying as a straight bar illustrated in FIGS. 15 and 16 has beenensured by means of a fixing pin 43. After the tension of the frame 30of the saw 10 and the tightening of the blade 20 have first been removedby lifting the lever part 34 in accordance with FIG. 16, the fixing pin43 is removed and the parts 31 a and 31 b of the front piece arecollapsible as shown in FIG. 17.

In FIG. 19, the lever part 34 is turned further, whereby the lever part34 approaches the blade 20 in FIG. 19 from below.

In FIG. 20, the saw 10 is in collapsed form, whereby the part 31 b ofthe handle part 31 and the lever part 34 form a cover for the blade 20.The teeth 25 of the blade 20 are covered in the groove of the lever part34 in the length of the lever part 34 so that the blade is covered fromthe direction of the teeth. The rest of the blade 20 goes into thegroove in the part 31 b of the handle part 31 from the back side of theblade 20. As the groove in the part 31 b is adequately deep, the blade20 is well covered in this position, too.

The saw 10 illustrated in FIG. 20 is turned into the sawing conditionaccordingly by turning the lever part 34 as shown in the embodiments ofFIGS. 11-14. This embodiment, however, requires a fixing for keeping thefront piece formed of two parts 31 a and 31 b straight in the situationof FIG. 16, when the blade 20 is tightened by turning the lever part 34.For that purpose, the saws of FIGS. 15-20 are provided with a fixing pin43. It can, however, as well be e.g. a spring-loaded fixing nail, whichautomatically fixes the parts 31 a and 31 b after they have been turnedto form a straight bar according to FIG. 16.

FIG. 21 illustrates in the sawing position a fifth embodiment of thecollapsible saw 10, wherein the lever part 34 is connected to the frontpiece 32 by means of a fulcrum pin 23. The lever part 34 has been turnedto be in connection with the support body 33, whereby the blade 20 istightened.

In FIG. 22, the collapsing of the saw 10 has been started by lifting thelever part 34 so that it turns around the fulcrum pin 23. Simultaneouslythe front piece 32 and the handle part 31 are turned around the fixingpins 21 a and 21 b of the blade 20, whereby the support body 33 startsapproaching the blade 20.

In FIG. 23, the lever part 34 has been turned further, whereby the blade20 remains inside the support body 33 and the lever part 34 approachesthe blade 20 in FIG. 23 from below.

In FIG. 24 the saw 10 is in collapsed form, whereby the blade 20 isinside the support body 33 and the lever part 34 is pressed onto theteeth 25 of the blade 20 for cover.

The saw 10 of FIG. 24 is brought to the sawing condition by turning thelever part 34 clockwise as illustrated in FIGS. 24 and 23. Thereby, thesupport surface 38 of the lever part 34 is supported onto thecorresponding surface of the front piece 32. When in the situationillustrated in FIG. 22 the lever part 34 is further turned clockwise,the lever part 34 is pressed between the halves of the two-piece supportbody 33, whereby the blade 20 is simultaneously tightened. The saw 30 isready for sawing when the fixing loop 39 of the support body 33 is fixedin the lever part 34.

FIG. 25 illustrates a sixth embodiment of the collapsible saw 10 insawing position as a side view. The lever part 34 is turned between thehalves of the two-piece support body 33, whereby the blade 20 istightened. The lever part 34 is connected to the front piece 32 by meansof a joint 29.

In FIG. 26 the collapsing of the saw 10 has been started by lifting thelever part 34, whereby the blade 20 is loosened and the shaft pin 23 inthe end of the support body 33 is movable in the conduit 35 arranged inthe front piece 32. When the support body 33 is moved towards the blade20, the handle part 31 simultaneously turns around the fixing pin 21 a.

In FIG. 27 the support body 33 and the handle part 31 have been movedonto the blade 20, whereby also the front piece 21 and the lever part 34are turnable onto the blade 20 for covering it, as shown in FIG. 28.

The saw 10 of FIG. 28 is brought into the sawing condition by turningthe lever part 34 and the handle part 32 connected thereto by means of ajoint 29 antidockwise into the position shown in FIG. 27. Thereby thesupport body 33 is liftable upwards so that the fulcrum pin 23 in theend of the support body 33 moves in the conduit 25 also upwards into theposition shown in FIG. 26. When the lever part 34 is after this turnedclockwise, the frame construction 30 is stretched and the blade 20 istightened in accordance with FIG. 25. After this, the saw is ready foruse.

The embodiments of the saw 10 illustrated in FIGS. 1-10 and 29-41 areespecially preferable, because in them the teeth 25 of the blade 20 arein a folded position hidden along the whole length of the blade 20 andcovered in the grooves of the handle part 31 and the lever part 34. Inthe other illustrated embodiments, the teeth 25 are actually covered,but there is no complete cover on them at the whole length of the blade20.

The lengths of the bow saws 10 in FIGS. 1-20 and 25-28 and 3641 are inthe collapsed form also mainly only the same as the length of the blade20. In the embodiments of FIGS. 21-24 and 29-35, the collapsed saw 10has a length slightly bigger than the length of the blade 20.

FIG. 29 illustrates in side view a seventh embodiment of the collapsiblesaw 10 in collapsed form. It can be seen in FIG. 29 that in thisposition the blade is totally covered by the parts of the frameconstruction 30 of the saw 10. These parts of the frame construction 30are a handle part 31, a front piece 32, a support body 33 and a leverpart 34. The saw 10 is opened and turned into the sawing condition byturning said parts of the frame construction 30 into another positionwithout having to detach any part of the saw 30 during this operation.

Bringing the saw 10 into the sawing condition is started by turning thelever part 34 and the handle part 31 connected thereto by means of afulcrum pin 24 anticlockwise in the way illustrated in FIG. 30. When thelever part 34 and the handle part 31 are further turned anticlockwiseinto the positions shown in FIGS. 31 and 32, it is noticed that in thisembodiment the handle part 31 is connected to the blade 20 by means ofan extension part 40 and a fulcrum pin 41. To the support body 33 thehandle part 31 is connected via a shaft part 37, in the way as shown inthe embodiments of FIGS. 7-10.

It is seen in FIGS. 33-35 that by means of the extension part 40, morespace is obtained for fingers of the sawyer in the zone of the handlepart 31. Thus, the whole length of the blade 20 may be utilized forsawing and the fingers of the operator do not touch the item beingsawed. This embodiment of the invention is most preferable when appliedto an iron saw.

It is seen in FIG. 34 that when the lever part 34 is further turnedanticlockwise, the handle part 31 approaches the fulcrum pin 22 of thesupport body 33 and the lever part 34 is turned around the fulcrum pin24 until the support surfaces 38 between the lever part 34 and thehandle part 31 touch each other stopping the turning motion of the leverpart 34 in relation to the handle part 31. Thus, the support surfaces 38define the angle, in which the lever part 34 and the handle part 31remain in their ultimate position, whereby the lever part 34simultaneously is fairly close to the support body 33.

The turning of the bar formed of the lever part 34 and the handle part31 together between the halves of the two-piece support body 33 into theposition shown in FIG. 35 requires some strength, whereby simultaneouslythe frame construction 30 of the saw 10 is stretched and the tighteningand tensile stress required for sawing are obtained in the blade 20.Finally, the lever part 34 is fixed in the handle part 31 by means of afixing loop 39, whereafter the saw 10 has been brought into the sawingcondition without having to detach any part of the saw 10 during theoperation.

Accordingly, the blade 10 illustrated in FIG. 35 is collapsible byperforming the operations illustrated in FIGS. 29-35 in reversesuccession. Even then, there is no need to detach any part of the saw 10and the blade 20 is nevertheless totally covered by means of the partsof the frame construction 30, as illustrated in FIG. 29.

FIG. 36 illustrates a side view of an eighth embodiment of thecollapsible saw 10 in collapsed form. This embodiment of the inventionis most preferable when applied in a wood saw, wherein when the saw 10is in the collapsed form, the blade of the saw is totally covered insidethe frame construction 30.

FIGS. 37-40 illustrate various stages of bringing the saw 10 into thesawing condition. This operation is performed so that all the parts ofthe frame construction 30 of the saw 10, the joints between the partsand the blade are in their places all the time and attached to eachother. FIG. 41 illustrates the saw 10 in the sawing condition.Accordingly, the collapsing of the saw 10 is performed so that all theparts of the frame construction 30 of the saw 10, the joints between theparts and the blade are in their places all the time and attached toeach other. No part of the saw 10 or the blade has to be detached orremoved during these operations.

In FIG. 37, the bringing of the saw into the sawing condition has beenstarted by turning the lever part 34 and the handle part 31anticlockwise in FIG. 37. The turning motion of these parts is continuedin accordance with FIG. 38, whereby simultaneously the front piece 32 isturned in relation to the support body 33 anticlockwise in the figurearound the fulcrum pin 23. In FIG. 39 the front piece 32 is turned tosuch an extent that the support surfaces 42 between the front part 32and the support body 33 touch each other, after which these parts are nomore turnable to this direction in relation to each other.

It is seen in FIG. 40, that also the support surfaces 38 between thelever part 34 and the handle part 31 touch each other, whereby the leverpart 34 also is no more turnable to this direction in relation to thehandle part 31. Now, the front part 32 and the support body 33 in thesaw 10 form a bar and the handle part 31 and the lever part 34 formanother bar. However, in this situation the lever part 34 is already soclose to the support body 33 that these parts can be manually pressedinto the proximity of each other. Simultaneously the required tension isobtained in the frame construction 30, which tightens the blade 20 ofthe saw for sawing purpose. The lever part 34 and the support body 33are fixed to each other by means of a fixing loop 39, after which thesaw 10 is in the sawing condition.

It is to be noticed that the fixing loop 39 between the lever part 34and the support body 33 is only an exemplary solution and the fixing mayjust as well be effected in some other corresponding way. Also theillustrated support surfaces between the parts of the frame constructionare exemplary solutions and may also be replaced by using othercorresponding solutions.

Thus, FIGS. 42-47 illustrate some details of examples for effecting thesupport surfaces 38 between the handle part 31 and the lever part 34 ofthe frame construction 30. In the illustrated examples, the handle part31 and the lever part 34 are turnable in relation to each other when thesaw 10 is brought into the sawing condition until their support surfaces38 a and 38 b are supported against each other. After that these partsare no more able to turn into this direction, but the parts togetherform a bar that can be used for tightening the blade 20 of the saw.

The example of FIGS. 48 and 49 relates to such a frame construction 30of the saw 10, wherein a shaft part 37 is arranged between the handlepart 31 and the support body 33. This kind of solutions are illustratede.g. in FIGS. 7-10 and 3641.

Additional Remarks

It is evident for a person skilled in the art that various embodimentsof the invention may vary within the scope of the appended claims.

LISTING OF REFERENCE NUMERALS

-   10 collapsible saw-   20 blade of the saw-   21 fixing pin-   22 fulcrum pin-   23 fulcrum pin-   24 fulcrum pin-   25 teeth-   26 fulcrum pin-   27 fulcrum pin-   28 fulcrum pin-   29 fulcrum pin-   30 frame construction-   31 handle part-   32 front piece-   33 support body-   34 lever part-   35 conduit-   36 groove-   37 shaft part-   38 support surface-   39 fixing loop-   40 extension piece-   41 fulcrum pin-   42 support surface-   43 fixing pin

1. A collapsible saw (10) comprising a blade (20) and a bow-like frame construction (30) formed of parts (31, 32, 33), to which frame construction (30) the blade (20) is attachable and which frame construction (30) can be turned into a smaller form for e.g. transportation purposes and to at least partly cover the blade (20) when the saw is not used, characterised in that the parts (31, 32, 33, 34) of the bow-like frame construction (30) of the saw 30 are connected to each other and the frame construction (30) is connected to the blade (20) by means of fixing members (21, 22, 23, 24, 35) at least one of which is a fulcrum pin (21, 22, 23, 24) allowing a turning motion between the parts, a bolt or corresponding, and/or at least one fixing member is a slide (35) or corresponding allowing a transfer motion between the parts so that the saw (10) is immediately collapsible and can again be brought into the sawing condition without detaching the parts of the frame construction or the fixing members therebetween.
 2. A collapsible saw (10) according to claim 1, characterised in that the frame construction (30) of the collapsible saw (10) comprises a lever part (34), by turning of which the bow part of the saw is collapsible and can be turned into a transportation position, and that by turning the lever part (34) into an opposite direction, the bow part of the saw can be turned into a sawing position, whereby the lever part (34) simultaneously acts as a tightening lever for the blade (20) of the saw.
 3. A collapsible saw (10) according to claim 1 or 2, characterised in that the turnable lever part (34) of the frame construction (30) is both a tightening lever for the blade (20) when the collapsible saw 10 is brought into the operating position and a cover for the teeth (25) of the blade (20) when the saw (10) is collapsed.
 4. A collapsible saw (10) according to claim 1, 2 or 3, characterised in that the lever part (34) turnable to cover the teeth (25) of the blade (20) is connected to the handle part (31) of the frame construction (30).
 5. A collapsible saw (10) according to any one of claims 1-4, characterised in that the lever part (34) turnable to cover the teeth (25) of the blade (20) is connected to the front piece (32) of the frame construction (30).
 6. A collapsible saw (10) according to any one of claims 1-5, characterised in that the length of the frame construction (30) of the collapsible saw (10) when collapsed corresponds essentially to the length of the blade (20).
 7. A collapsible saw (10) according to any one of claims 1-6, characterised in that the shape of the frame construction (30) of the collapsible saw (10) in the sawing condition is essentially a quadrangle, such as a rectangle or a parallelogram, and that the frame construction (30) in collapsed form has essentially the shape of the blade and is only slightly bigger than the blade (20).
 8. A collapsible saw (10) according to any one of claims 1-7, characterised in that when collapsing the frame construction (30) of the saw (10), the lever part (34) turns to cover the blade (20) from the side of the teeth (25).
 9. A collapsible saw (10) according to any one of claims 1-7, characterised in that when collapsing the frame construction (30) of the saw (10), the lever part (34) is turned to cover the blade (20) form the side opposite to the teeth (25). 